Description

In the Linux kernel, the following vulnerability has been resolved:

LoongArch: Update cpu_sibling_map when disabling nonboot CPUs

Update cpu_sibling_map when disabling nonboot CPUs by defining & calling
clear_cpu_sibling_map(), otherwise we get such errors on SMT systems:

jump label: negative count!
WARNING: CPU: 6 PID: 45 at kernel/jump_label.c:263 __static_key_slow_dec_cpuslocked+0xec/0x100
CPU: 6 PID: 45 Comm: cpuhp/6 Not tainted 6.8.0-rc5+ #1340
pc 90000000004c302c ra 90000000004c302c tp 90000001005bc000 sp 90000001005bfd20
a0 000000000000001b a1 900000000224c278 a2 90000001005bfb58 a3 900000000224c280
a4 900000000224c278 a5 90000001005bfb50 a6 0000000000000001 a7 0000000000000001
t0 ce87a4763eb5234a t1 ce87a4763eb5234a t2 0000000000000000 t3 0000000000000000
t4 0000000000000006 t5 0000000000000000 t6 0000000000000064 t7 0000000000001964
t8 000000000009ebf6 u0 9000000001f2a068 s9 0000000000000000 s0 900000000246a2d8
s1 ffffffffffffffff s2 ffffffffffffffff s3 90000000021518c0 s4 0000000000000040
s5 9000000002151058 s6 9000000009828e40 s7 00000000000000b4 s8 0000000000000006
ra: 90000000004c302c __static_key_slow_dec_cpuslocked+0xec/0x100
ERA: 90000000004c302c __static_key_slow_dec_cpuslocked+0xec/0x100
CRMD: 000000b0 (PLV0 -IE -DA +PG DACF=CC DACM=CC -WE)
PRMD: 00000004 (PPLV0 +PIE -PWE)
EUEN: 00000000 (-FPE -SXE -ASXE -BTE)
ECFG: 00071c1c (LIE=2-4,10-12 VS=7)
ESTAT: 000c0000 [BRK] (IS= ECode=12 EsubCode=0)
PRID: 0014d000 (Loongson-64bit, Loongson-3A6000-HV...

Classification

CVE ID: CVE-2024-26841

Affected Products

Vendor: Linux

Product: Linux

Exploit Prediction Scoring System (EPSS)

EPSS Score: 0.05% (probability of being exploited)

EPSS Percentile: 17.83% (scored less or equal to compared to others)

EPSS Date: 2025-02-04 (when was this score calculated)

References

https://git.kernel.org/stable/c/b1ec3d6b86fdd057559a5908e6668279bf770e0e
https://git.kernel.org/stable/c/0d862db64d26c2905ba1a6a8561466b215b664c2
https://git.kernel.org/stable/c/752cd08da320a667a833803a8fd6bb266114cce5

Timeline